Circular polarized antenna, semiconductor module, and wireless communication device

Abstract

A circular polarized antenna includes: a conductor ground plate; first and second monopole conductor elements; and a feed point provided at one of first and second connection points, wherein a first and second parts of the antenna are configured to be symmetrical with respect to a straight line passing between open ends of the first and second monopole conductor elements, wherein the first part includes: (1) a first half of the conductor ground plate formed on one side of the straight line including the first monopole conductor element; and (2) the first monopole conductor element, and wherein the second part includes: (3) a second half of the conductor ground plate formed on the other side of the straight line including the second monopole conductor element; and (4) the second monopole conductor element.

1 . A circular polarized antenna comprising:
 a conductor ground plate that is formed with an opening;   first and second monopole conductor elements that are formed in L-shape having substantially the same length, the first and second monopole conductor elements being respectively connected to the conductor ground plate at first and second connection points; and   a feed point provided at one of the first and second connection points,   wherein the first and second monopole conductor elements are arranged to be substantially orthogonal to each other, and open ends of the respective first and second monopole conductor elements are arranged to be adjacent to each other,   wherein a first part and a second part of the antenna are configured to be symmetrical with respect to a straight line passing between the open ends of the first and second monopole conductor elements, the straight line being substantially perpendicular to a line connecting the first and second connection points,   wherein the first part includes: (1) a first half of the conductor ground plate formed on one side of the straight line including the first monopole conductor element; and (2) the first monopole conductor element, and   wherein the second part includes: (3) a second half of the conductor ground plate formed on the other side of the straight line including the second monopole conductor element; and (4) the second monopole conductor element.   
   
   
       2 . The antenna according to  claim 1 , wherein the first connection point is provided on a first edge included in the first half of the conductor ground plate and the second connection point is provided on a second edge included in the second half of the conductor ground plate, the first and second edges being arranged to be substantially perpendicular to each other,
 wherein the opening formed on the conductor ground plate has: [A] a first nearest edge that is nearest to the first edge of the conductor ground plate; and [B] a second nearest edge that is nearest to the second edge of the conductor ground plate, and   wherein the first and second nearest edges of the opening are respectively arranged to be in parallel to the first and second edges of the conductor ground plate.   
   
   
       3 . The antenna according to  claim 2 , wherein the first connection point is provided at substantially center of the first edge, and
 wherein the second connection point is provided at substantially center of the second edge.   
   
   
       4 . The antenna according to  claim 3 , wherein the conductor ground plate and the opening are formed in square shape. 
   
   
       5 . The antenna according to  claim 2 , wherein the conductor ground plate has a corner being cut away in a square shape at an intersection point of the first and second edges. 
   
   
       6 . The antenna according to  claim 4 , wherein the conductor ground plate has all four corners being cut away in a square shape to be in a cross shape. 
   
   
       7 . The antenna according to  claim 1  further comprising:
 third and forth monopole conductor elements that have substantially the same length and are respectively connected to the conductor ground plate at third and forth connection points, the third and fourth monopole conductor elements being arranged at positions opposite the first and second conductor elements with respect to a center of the conductor ground plate; and   a second feed point provided at one of the third and fourth connection points.   
   
   
       8 . The antenna according to  claim 1 , wherein the conductor ground plate and the first and second monopole conductor elements are formed on a same plane. 
   
   
       9 . The antenna according to  claim 1 , wherein the first and second monopole conductor elements have a length of substantially a quarter wavelength of an operating frequency of the antenna. 
   
   
       10 . A circular polarized antenna comprising:
 a conductor ground plate with an opening and including a first plate and a second plate being symmetrical with respect to a straight line passing a center of the opening, the first plate having a first connection point and the second plate having a second connection point, a line connecting the first and second connection points being substantially perpendicular to the straight line;   first and second monopole conductor elements that are formed in L-shape having substantially the same length and being disposed symmetrically with respect to the straight line, the first monopole conductor element being connected to the first plate at the first connection point and the second monopole conductor element being connected to the second plate at the second connection point; and   a feed point provided at one of the first and second connection points,   wherein the first and second monopole conductor elements are arranged to be substantially orthogonal to each other, and open ends of the respective first and second monopole conductor elements are arranged to be adjacent to each other.   
   
   
       11 . A semiconductor module comprising:
 a dielectric substrate; and   the antenna according to  claim 1  being placed on the dielectric substrate.   
   
   
       12 . A wireless communication device comprising:
 the antenna according to  claim 1 ; and   a wireless communication circuit that is placed on the conductor ground plate of the antenna.